1. Field of the Invention
The present invention relates to a microwave oven and method of controlling the same that is capable of performing cooking using electrical heaters.
2. Description of the Related Art
Microwave ovens are generally provided with magnetrons that generate microwaves and cook food by heating the food using the microwaves.
When cooking is performed using only microwaves generated from the magnetron, the microwaves may not uniformly radiate the food according to a water content, a distribution and a size of the food, so the food may not be satisfactorily cooked. Further, various kinds of cooking may not be performed. For this reason, electrical heaters (hereinafter simply referred to as “heaters”) are installed in the cooking cavity of the microwave oven, so heat generated from the heaters is transferred to the food while the microwaves generated from the magnetron also radiate the food. Accordingly, the food is quickly and uniformly cooked.
The heaters installed in the microwave oven are fixedly positioned in respective predetermined portions of a cooking cavity, but the respective predetermined positions of the heaters may not be changed according to a volume and the size of the food. Accordingly, the heaters need to be rotatably installed to more satisfactorily cook the food. Further, the heaters need to be rotatably installed to allow the food to be easily put into or taken out of the cooking cavity.
A microwave oven has been developed in which the heaters are, respectively, horizontally positioned in a cooking mode wherein cooking by heating of the heaters is performed, while the respective positions of heaters may be changed using a motor so that the heaters are, respectively, positioned in predetermined portions of the cooking cavity in cooking modes when the heaters are not used. In the microwave oven, respective positions of the heaters are detected using two micro switches so as to detect the respective positions where the heaters are used, for example, respective horizontal positions where the heaters are horizontally positioned, and positions where the heaters are not used, for example, respective vertical positions where the heaters are vertically positioned.
As described above, the microwave oven is provided with the micro switches of a number equal to a number of cooking modes of the microwave oven. As more heaters are installed in the microwave oven, more micro switches should be provided to detect the respective positions of the heaters, so the microwave oven is disadvantageous in that a manufacturing cost thereof is increased.
Further, when the microwave oven is provided with a plurality of micro switches, detection signals of the plurality of micro switches are transferred through corresponding electrical wires to corresponding input terminals of a microcomputer. In this case, the electrical wires may be incorrectly connected to the plurality of micro switches in an assembly process. For example, in a case where a plurality of electrical wires are connected to the plurality of micro switches that detect the respective vertical and horizontal positions of the heaters, the respective vertical and horizontal positions of the heaters are incorrectly detected in the microcomputer if the plurality of electrical wires are incorrectly connected to the corresponding micro switches due to manufacturing errors by a producer. Thus, cooking is performed with the heaters inappropriately positioned in the cooking cavity, so the cooking may not be adequately performed.